Calculating apparatus.



A. B. HERRIGK.

GALCULATING APPARATUS.

APPLIGATION FILED MAY 7, 190s.

Patented Feb. 17, 1914.

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CURRENT N AMPERES.

INVENTOR. ,4MM/*HIM 3y ATTORNEYJ ing Apparatus, t .a full, clear, andexact specification.

' paratus 'sides of a rectangle ALBERT B.

HERRICK, OF'RIDGEWOOD, NEW JERSEY.

GALCULATING APPARATUS.

Specification of Letters Patent.

Patented Feb. 17, 1914.

l Application led May 7, 1908. Serial No. 431,350.

To all whom it may concern Be it known that I, ALBERT B. HERRICK, acitizen of the United States, residing at Ridgewood, in the county ofEssex and State of New Jersey, have invented certain new and usefulImprovements in Calculatof which the following is This invention relatesto calculating apparatus, and has particular reference to an apparatusadapted for the graphical solution of typical equations wherein onequantity is unknown and three or more are known. A convenient means forthe graphic solution of such'equations, without the necessityof.calcnlation, is desirable, especially in engineering problems, suchas horsepower calculations, wiring, property of beams, fills, etc. Suchequations have the general form d vide an apparatus wherein -theseequations can be graphically solved, three of the pfactors being known.The presence of one or more constants in the equation does not affectthe result when they are fixed for the whole equation. By the sameapparatus, equations of the general form AXBXCID may be solved b usingthe reciprocal of one or more of the actors.

In carrying out the invention, the four are each divided into scales,each representing one ofthe factors of the equation, and the rectangleis itself divided .by lines radiating from a center, either within lthechart or outside of it as the special problem requires. By causing thesescales and radial lines to bear a functional relation to the equation tobe solved, it is possible to solve a great variety of equations, varyingaccording to the scales employed.

In solving different kinds of problemsyas horse-power and wiring, forinstance, different scales are necessary, and in order to increase therange of usefulness of the apparatus, I have provided a calculatingapembodying a plurality of scales, and preferably so interconnected thatscales suitable for one range of problems may be simultaneously shiftedto scales suitable for the other range of roblems.

The invention wil be more full understood in connection with thedescription of the accompanying drawings, wherein- Figure 1 is a view ofan apparatus embodying the invention; Fig. 2 is a view with the faceplate removed, showing themovable scale plates; Fig. 3 shows a scalearranged according to reciprocals; a cross section; Fig. 5 is a detailend view; and Fig. 6 is a detail showing the connection of movable scaleplates. v

1 represents the base plate having raised corners Q, forming guidewaysor spaces 3 in which slide scale plates 4, 5. The scale plate 4 slidesvertically, and the scale plate 5 transversely between the corners 2. In

order to operate the scale plates simultaneously, there is pivoted at 6to plates 4, an operating lever 7, which is pivoted to plate 5 at 8, thelever '7 lying between the plates f1, 5, so that when the lever is movedbetween the stops 9, 9 on base plate 1, the plate 1 will be movedvertically, and the pla'te 5 simultaneously horizontally. As will beseen in Fig. 2, the plate 4 has four scales B at one end and four scalesD at the other end, and the plate 5 has four scales A at one end, andfour scales C at the other end, whereby four different kinds of problemscan be solved b shifting the operating lever 7 to four di erentpositions, and thereby bringing the corresponding scales, havingfunctional relation with each other, into proper positions. As manydifferent sets of scales may be used as there are ranges of the problemwhich it is desired to work out with a single device, the scales foreach range of problems bearing a functional relation to each other, asin Fig. 1 where scale A represents distance in feet, B current inamperes, C drop in volts, and D size of wire.

Referring now to Fig. 1, showing the complete apparatus, the face plate1() has slots 11 through which the scales A, B, C, D, appear, when theyare properly set by the lever 7 and the indicating notch 12. Therectangle formed by the four slots is laid out into squares proportionedto indicate units of measure. Near one of the corners of the rectangleis the center from which radii are drawn to the division marks. The zeroof scales B and C is at this center, while zero on scales A and D are onthe orn `reci roczil of the thiifdi se aibscissa from this slime center.il `will be understood that the values ilor i. irce oi the seules: canbe laid sul; for the range i the problems: required but related to euchother iis the ij'erliiuhe connecting them, and vvalims el the .fourthscale figur d out from the other three. herein shown, the values oitscale l) have been ce culzited and plotted frein the values assumed forscales il., Bt C and this will be done i'nr each kind et problem Where`iiliilereni scales having different- Ynlues are required. lt will beunderstood that velues having been taken for any three of the s -files,the fourth must be es.n culsit-ed und plotted therefrom, in order tosolve all problems Within the range of a given set olf scales.

rThe scales Si, IB, D, of Fig. l, are marked respectively :for distancein feet for s ninin, current in snip/eres, drepin Volts, and size ofWire in circular mils, and with such scales and `the diagonal linesj itis possible to nml-:c Calculations graphically t0 determine any one oit'these quantities, if the other three be known. rlhus suppose it desiredte ascertain the size oit wire. neces sary t0 en /fry L current oit 50sniperes for 1500 feet, with s, drop 0f say six volts. The current inainperes multiplied by twice the distance in feet, multiplied by :iconstant fer the resistance per mil feet md divided by the diep in veltsequals the circulaiares of the necessary Wire, which een be read efffrom the scale To do thisD find the Cliagonsl passing through the pointWhere the horizontal line' ici in the division G 0f scale C meets thevertiesl line lroin division of scale l then up 03? down en this cli--agenzil until ith: he; ze.

vision l5 of seele and ay vertical line upward fr est intersection willintersect seele :u zit about the division 260,@00, which is 'thesolution. it should be herne in innd that the (AXE) must be on thediagonal, and the -der (C) on the, opposite side, the fourth quantitywhich is read el? beingon the side Twith the divisor. Thus C can beascertained if ji. B l? be known by tslzi A and B as multipliers, anddividing hy L. op c 1g this apparatus, it essential 'te selec?. twe ofAlie three known values lying' en opp-site sides of the diagonal, is ndC, or i-L and D is multipliers. These values lying on the ssii of thedizigenel, as A and B, or C and lj, will not ce" e y solve problems, ifused is multipliersu 'new itbe desired to solve problems wherein lthreequantities inu'st be two multipliers saine side ot the suflice, foi thisapparatus requires that one of the factors be s diviser. To multiplythree quantities together is 'the ss diM riding the pioduct of tir-e cithefn 'the :hat by laying mesme/ii;

assume 't prcssu l A Volvecly three o" presence of ene er .uieeAcenetants equi-tien does not liest 'the investies i here they are simuit will le secr plates solves iylzi su, d lng predetermined tional L .cuch problei mining enl7 suc tho device een Li iiiereby u' za ud desu pfeuch to said lines te permit :12m-res i l e be i:

angles .seis ehi' 3. A calculating apparatus comprising a plate providedwith slots at two of its sides, and a pair of slides having sets ofscales mounted to move in directions at right angles to said two sidesof said plate to bring different sets of scales into alinement with saidslots, and means for moving said scales simultaneously.

4. A calculating apparatus comprising a plate having a rectangle markedthereon, a plurality of movable scale plates for each side of saidrectangle, an operating lever connected to both scale plates whereby tomove them simultaneously at right angles to each other, and a pluralityof sets of scales on each scale plate, the scales of each set4 bearing afunctional relation to each other.

5. A' calculating apparatus comprising a plate havin a rectangle markedthereon, a plurality o movable scale plates for each side of saidrectangle, an operating lever connected to both scale plates whereby tomove them simultaneously at right angles to each other, a plurality ofsets of scales on each scale plate, the scales of each set bearing afunctional relation to each other, said operating lever having anindication corresponding to each set of scales, and indicating means onthe plate.

6. A calculating apparatus, comprising a plate having cross-sectionlines and diagonal lines, at least three sides of said plate beingprovided with slots, a slide mounted at each of said sides of saidplate, said slides carrying a plurality of corresponding sets of scalesrepresenting at least three different quantitles bearing a functionalrelation to each other, and means for simultaneously movin said slidesto bring corresponding sets o scales into view.

7 The combination of a face plate of four sides and having cross-sectionlines and diagonal lines, the four sides of said face plate beingprovided with slots, a plurality of plates carrying a plurality ofcorresponding series of designations, and means for simultaneouslymoving said plates relative to the face plate so that correspondingseries of designations on said plates can be read through said slots.

8. A calculating apparatus comprising a plate havinor intersecting linesthereon, a plurality ofD members each having corresponding sets ofscales indicated thereon, the divisions of each of said scalescorresponding to said lines, said plate being cut away to permitcorresponding scales on said members to be visible at a time, a commonmeans for shifting said members to bring to view a different set ofscales, and means for 'indicating the nature of the set of scalesbrought to view.

In testimon whereof l aiiix my signature, in presence o two witnesses.

ALBERT B. HERRICK. Witnesses: JULIAN S. Woos'rER,

GEO. A. HOFFMAN.

Copies of this patent may be obtained for ve cents each, by addressingthe Commissioner ot Patents. Washington, D. C.

